How in the script to apply an image on the image texture node
The solution was quite simple, though not found answer on the Internet.

import bpy
bpy.data.images.load("D:/badge/temp/1.png", check_existing=True)
mat = bpy.context.view_layer.objects.active.active_material
tex = bpy.data.images.get('1.png')
image_node = mat.node_tree.nodes["Image Texture"]
image_node.image = tex


At the same time, the desired node must be selected previously in the material so that everything works out.